       Document 0388
 DOCN  M9590388
 TI    Differential susceptibility of fresh human monocytes and cultured
       macrophages to HIV-1 infection in vitro.
 DT    9509
 AU    Sonza S; Maerz A; Lewin S; Mills J; Crowe S; Macfarlane Burnet Centre
       for Medical Research, Fairfield,; Victoria.
 SO    Annu Conf Australas Soc HIV Med. 1994 Nov 3-6;6:100 (unnumbered
       abstract). Unique Identifier : AIDSLINE ASHM6/95291711
 AB    We have investigated the susceptibility of peripheral blood monocytes to
       infection with HIV-1 in vitro. Although monocytes express high levels of
       CD4 on their surface on the day they are isolated, they are resistant to
       infection, measured by the production of p24 antigen. However, following
       some time in culture, they become readily susceptible even though their
       CD4 expression is much lower. To determine how soon after isolation
       monocytes became readily susceptible to infection, PCR analysis of cDNA
       synthesis was performed. While freshly isolated monocytes failed to
       initiate cDNA synthesis following pulsing with HIV-1, full length
       reverse transcripts were detectable within 24 h of infection of
       monocytes which had been cultured for one or more days prior to
       infection. Productive infection, as measured by p24 antigen
       accumulation, ensued in these cultured cells. Employing a novel PCR
       method, evidence was also found for rapid integration of proviral DNA
       following cDNA synthesis in susceptible cells. This differential
       susceptibility of fresh compared to cultured monocytes was not an
       artefact of the use of laboratory-adapted strains but held true also for
       primary patient macrophage-tropic isolates. In contrast, tissue
       macrophages (alveolar and placental), which have low CD4 expression,
       were susceptible to infection immediately upon isolation without prior
       culture. There is, therefore, a block to HIV-1 infection in fresh
       monocytes, prior to the commencement of reverse transcription, which is
       overcome by overnight culture and which does not occur in macrophages
       differentiated in vivo.
 DE    Cells, Cultured  Human  HIV Core Protein p24/ANALYSIS
       HIV-1/IMMUNOLOGY/*PATHOGENICITY  Macrophages/IMMUNOLOGY/*VIROLOGY
       Monocytes/IMMUNOLOGY/*VIROLOGY  Reverse Transcriptase/ANALYSIS  Virus
       Replication/IMMUNOLOGY  MEETING ABSTRACT

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

